sphygm-

From the Ancient Greek σφυγμός (sphugmós, “pulse”), from σφύζω (sphúzō, “I beat”, “I throb”).

• (Received Pronunciation) enPR: sfĭgʹm, IPA^(key): /ˈsfɪɡm/

sphygm-

1. (medicine and physiology) pulse, pulsation (of blood delivered by the beating heart)

• When combined with a word or another affix which begins with a consonant, this prefix concatenates with -o- (as sphygmo-).

• sphygmic
• sphygmics

• “Sphygmo-” listed on page 588 of volume IX, part I (Si–St) of A New English Dictionary on Historical Principles [1st ed., 1919]
  Sphygmo- (sfi·gmo), a. Gr. σφυγμο-, combining form of σφυγμός pulse (f. σφύζειν to beat or throb), used in various scientific terms: [11 derived terms, viz. sphygmodynameter, sphygmogram, sphygmograph, sphygmographic, sphygmography, sphygmomanometer, sphygmometer, sphygmometric, sphygmophone, sphygmophonic, sphygmoscope; ¶; 22 quots.: 1876, 1887, 1898, 1860, 1875, 1897, 1870, 1879, 1895, 1859, 1864, 1891, 1898, 1842, 1872, 1899, 1898, 1879, 1889, 1881, 1859, 1862]
• “sphygmo-” listed in the Oxford English Dictionary [2nd ed., 1989]